This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Skin, as a source for cell replacement therapies, offers formidable advantages such as accessibility and innate organ regenerative potential. Skin as an autologous source of somatic stem cells can circumvent the quintessential immunogenic rejection associated to heterologous cell replacement therapies. In vitro differentiation of skin derived progenitor (SKP) cells produce cells of neural and glial lineages. Little is known about the mechanisms by which the decision of lineage commitment is made. It is known that upon in vitro differentiation, higher proportions of glial cells are produced. In neural progenitor cells from the central nervous system (CNS) of mouse and rats the lineage determination and onset of differentiation is controlled by methylation changes of genomic DNA. The working hypothesis of the proposed work is that an induced hypo-methylation in the genomic DNA of the SKP will shift their gene and protein expression profile towards a neuronal lineage. In vivo and in vitro evidence suggests that inhibition of DNA methyltransferases alters the onset and determination of.the glial-astrocytic lineage. With the use of a DNA methyltransferases inhibitor 5-aza-deoxycytidine as a pharmacological tool, we intend to de-methylate the genomic DNA of the SKP from Rattus norvegicus neonates. We expect that the in vitro de-methylation will induce a higher proportion of SKP derived cells to differentiate into neurons. The change in phenotype towards neurons will be explored by ascertaining the changes observed in multiple neural gene expression and protein markers. In vitro regulation of SKP cell differentiation offers a good opportunity to further study how epigenetic mechanisms control cell differentiation. Understanding the role of epigenetic mechanisms on cell differentiation also allows for optimization of in vitro conditions to use the skin as an autologous source of neurons for cell replacement therapy of neurological disorders.